O’Hagin Vent Calculator

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Step 1: DETERMINE SQUARE FEET OF CODE-REQUIRED VENTILATION
÷ Compliance Method
Step 2: CONVERT SQUARE FEET OF CODE-REQUIRED VENTILATION TO SQUARE INCHES
x 144 = Total Square inches of Code-Required Ventilation
Step 3: DETERMINE THE ADEQUATE NUMBER OF O’HAGIN VENTS REQUIRED
Total O’Hagin Vents Required for sq. inches:
O’Hagin Tapered Low-Profile
72.0 sq. in NFVA

Vents High:
Vents Low:
O’Hagin High-Profile Model S
97.5 sq. in NFVA

Vents High:
Vents Low:
O’Hagin Low/Medium Profile Model M
86.25 sq. in NFVA

Vents High:
Vents Low:
O’Hagin Low-Profile Model Flat
98.75 sq. in NFVA

Vents High:
Vents Low:
MANUFACTURER’S RECOMMENDATIONS
The patented O’Hagin Balanced Ventilation System utilizes O’Hagin vents placed strategically within the field of roofing material both high (near the ridge for exhaust) and low (near the eave for intake). This strategic high and low placement of O’Hagin vents allows the balanced system to fully optimize both wind and thermal effects to provide superior passive ventilation throughout the attic. Additionally, placement of O’Hagin vents both high and low should provide an equal, balanced rate of ventilation performance in each area. The calculations above do not include any potential Net Free Ventilation Area (NFVA) values provided by alternative ventilation methods that may be present in any specific structural design.
O’Hagin Vent Calculator
Step 1: DETERMINE SQUARE FEET OF CODE-REQUIRED VENTILATION
Square Feet: ÷ Compliance Method: =
= Total Square Feet of Code Required Ventilation
Step 2: CONVERT SQ. FT. OF CODE-REQUIRED VENTILATION TO SQ. IN.
x 144 = Total Square inches of Code-Required Ventilation
Step 3: DETERMINE QUANTITY OF O’HAGIN VENTS REQUIRED
Total Vents Required for sq. inches:
Tapered Low-Profile
72.0 sq. in NFVA
Vents High:
Vents Low:
High-Profile Model S
97.5 sq. in NFVA
Vents High:
Vents Low:
Low/Med Profile Model M
86.25 sq. in NFVA
Vents High:
Vents Low:
Low-Profile Model Flat
98.75 sq. in NFVA
Vents High:
Vents Low:
MANUFACTURER’S RECOMMENDATIONS
The patented O’Hagin Balanced Ventilation System utilizes O’Hagin vents placed strategically within the field of roofing material both high (near the ridge for exhaust) and low (near the eave for intake). This strategic high and low placement of O’Hagin vents allows the balanced system to fully optimize both wind and thermal effects to provide superior passive ventilation throughout the attic. Additionally, placement of O’Hagin vents both high and low should provide an equal, balanced rate of ventilation performance in each area. The calculations above do not include any potential Net Free Ventilation Area (NFVA) values provided by alternative ventilation methods that may be present in any specific structural design.
Visit us online at Ohagin.com for more information or call us at: (877) 324-0444